Propulsion apparatus for underwater driving

ABSTRACT

A propulsion apparatus for underwater driving comprising a driving unit housing having a motor embedded therein. A propulsion unit housing connected to the driving unit housing, having a plurality of inlet holes formed therein in a radius direction, and having a driving shaft for rotating a propeller using power received from the propeller and the motor.

CROSS REFERENCE TO RELATED APPLICATION

The present application claims a priority to International Application PCT/KR2012/008068, with an International Filing Date of Oct. 5, 2012, which claims the benefit of Korean Patent Application No. 10-2012-0100902 filed with the Korean Intellectual Property Office on Sep. 12, 2012, the entire contents of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Technical Field

The present invention relates to a propulsion apparatus for underwater driving and, more particularly, to a new type of a propulsion apparatus for underwater driving, which has been improved to enable safe propulsion by further enhancing water tightness in a propulsion apparatus having a driving unit and a propulsion unit integrated therein wherein a driving motor, that is, a power source, and an impeller, that is, a propellant, are integrated to reduce a loss of rotational movement and maximize propulsion efficiency.

2. Description of the Related Art

In general, a propulsion apparatus for underwater driving is an apparatus that enables an electric boat, a submerged scooter, a submarine, and other underwater equipment to have mobility under the water.

Propulsion apparatuses mounted on an electric boat, a submerged scooter, a submarine, and other underwater equipment as described above and used on the water or under the water may be classified according to a propulsion type, materials for the hull, and purposes of the propulsion apparatuses for underwater driving.

In general, in the case of classification according to a propulsion type of the propulsion apparatus for underwater driving, various forms are used, but a propulsion apparatus using a propeller is chiefly used.

Here, the propeller is rotated at specific speed by way of driving force supplied from an engine or a driving source, and the rotating propeller moves a fluid, thereby propelling the hull under the water.

For another example, there is a water jet propulsion method of obtaining propulsion force by leading water through an inlet port that is opened in the bottom of a ship, changing the led water into a swirling flow by pressurizing the led water using an impeller, rectifying the swirling flow into a straight-line flow through a diffuser, and spraying the straight-line flow in a water jet form through a stern.

Meanwhile, with the help of recent marine leisure culture, submerged scooters capable of freely moving on the surface of the water and under the water are actively spread. A propeller type propulsion apparatus is basically mounted on such a submerged scooter.

This is because it is difficult to apply the water jet propulsion method to small-sized equipment for reports, such as a submerged scooter, from various aspects in terms of the structure, volume, and cost because the water jet propulsion method is chiefly applied to the hull having a complicated structure and a large volume and requiring high-speed propulsion.

However, since a common propulsion structure is a structure in which the propeller is exposed to the stern, there are problems in that ascidians are caught in the propeller, with the result that the propeller is likely to be damaged, a submerged scooter is turned over or becomes an inoperable state, and a high risk is caused. Furthermore, there is a problem in that a diver may be injured due to an immature manipulation.

In order to solve such problems, the applicant of the present invention has disclosed Korean Patent Laid-Open Publication No. 2012-0034887, which has improved safety and propulsion force by embedding a propeller and integrating the propeller and a motor while maintaining an impeller form.

However, there is a limitation that strict water tightness is necessary in terms of a structural characteristic in driving under the water because the driving unit and the propulsion unit are integrated and responsible for a propulsion function.

That is, the driving unit commonly refers to a motor function, and the motor requires very strict water tightness because the driving unit is driven by electricity and thus a severe driving failure is caused if minute water leakage occurs under the water.

Accordingly, there is a need to further reinforce the water tightness part of the above Korean Patent Laid-Open Publication disclosed by the applicant of the present invention.

SUMMARY OF THE INVENTION

The present invention has been invented owing to a necessity to reinforce water tightness described above, and a main object of the present invention is to provide a propulsion apparatus for underwater driving, which can prevent a loss of power and a fluctuation upon high-speed rotation and provide stable propulsion force and high propulsion efficiency by directly connecting an impeller responsible for a propulsion function to the motor without coupling, can integrally implement a driving unit and a propulsion unit in order to improve the efficiency of a motor and secure the easiness of control, and can fully secure safety when the propulsion apparatus is used under the water by separating a stator and a rotator that form the driving unit using a diaphragm unlike already disclosed structures so that an almost perfect watertight structure can be achieved.

The present invention provides, as means for achieving the object, a propulsion apparatus for underwater driving, including a driving unit housing 100 having a motor embedded therein and a propulsion unit housing 200 connected to the driving unit housing 100, having a plurality of inlet holes 240 formed therein in a radius direction, and having the propeller 220 and a driving shaft 210 for rotating a propeller 220 using power received from the motor, wherein the motor includes a stator 110 and a rotator 120; the stator 110 has a coil wound on a core, and the rotator 120 has a permanent magnet; one end of the driving shaft 210 is integrally fixed to the rotator 120 through the center of the rotator 120; the rotator 120 and the stator 110 are separated by a separation diaphragm 140, and the separation diaphragm 140 is fixed to and supported by a diaphragm bracket 150 fixed to the driving unit housing 100 so that an air gap is provided between the separation diaphragm 140 and the rotator 120; and the end of the driving shaft 210 remains spaced apart from the separation diaphragm 140, and part of one side of the rotator 120 is concaved so that a space S is formed between the separation diaphragm 140, the driving shaft 210, and the rotator 120.

Here, the air gap is 0.5 to 1.5 mm.

Furthermore, an orifice is formed on the rotator 120 and configured to discharge water introduced into the space S to a space outside the rotator 120 on an opposite side to the separation diaphragm 140.

Furthermore, a surface of the rotator 120 is subject to waterproof coating.

Furthermore, the driving shaft 210 is rotated and supported by a pair of front and rear bearings 132 and 134 and integrally fixed to the rotator 120 through a center of the rotator 110, and the stator 110 is separated from the driving shaft.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exemplary perspective view of a submerged scooter on which a propulsion apparatus for underwater driving in accordance with the present invention has been mounted.

FIG. 2 is an exemplary side view of the submerged scooter on which the propulsion apparatus for underwater driving in accordance with the present invention has been mounted.

FIG. 3 is a cross-sectional view of an exemplary installation structure of the propulsion apparatus for underwater driving in accordance with the present invention.

DETAILED DESCRIPTION

Hereinafter, a preferred embodiment of the present invention is described in more detail with reference to the accompanying drawings.

Prior to a description of the present invention, specific structural and functional descriptions hereinafter have been merely illustrated to describe embodiments according to the concept of the present invention. The embodiments according to the concept of the present invention may be implemented in various forms and should not be construed as being limited to the embodiments described in this specification.

Furthermore, the embodiments of the present invention may be modified in various ways and may have several forms, and thus specific embodiments are illustrated in the drawings and are described in detail in this specification or the application. An embodiment according to the concept of the present invention is not intended to be limited to a specific disclosure, and it is to be understood that the embodiment includes all changes, equivalents, and substitutions which fall within the spirit and technical scope of the present invention.

As shown in FIGS. 1 and 2, a propulsion apparatus for underwater driving in accordance with the present invention is mounted on the back of the stern of a hull 10 that forms a submerged scooter.

Here, the hull 10 generally has a streamline shape, and the hull is configured so that a diver can operate the submerged scooter by grasping a handle 20 in the state in which the diver has lain on the top of the hull 10.

Furthermore, the propulsion apparatus for underwater driving in accordance with the present invention has a driving unit and a propulsion unit integrally implemented and includes a driving unit housing 100 and a propulsion unit housing 200, as shown in FIGS. 1 to 3.

In this case, a motor is embedded in the driving unit housing 100, and a driving shaft 210 rotated in response to power of the motor and a propeller 220 fixed to the driving shaft 210 and configured to generate propulsion force while being rotated along with the driving shaft 210 are embedded in the propulsion unit housing 200.

Furthermore, the driving unit housing 100 and the propulsion unit housing 200 are combined in such a way as to be separated and assembled together.

Meanwhile, the motor is a Permanent Magnet Alternative Current (PMAC) motor unlike in the prior art and is an AC motor. A stator 110 and a rotator 120 are provided in the motor in such a way as to face each other.

In particular, voltage can be easily converted and safety can be maximized because the generation of an arc is obviated by using an AC motor not a DC motor.

Here, the stator 110 has a coil wound on a core. The stator 110 is firmly fixed to the inside of the driving unit housing 100 by means of a front bracket 112 that seals and fixes one side of the driving unit housing 100. The rotator 120 is configured to have a permanent magnet attached to its disk plate and installed to be rotatable in the state in which the rotator 120 has been integrally fixed to the driving shaft 210 while facing the stator 110.

In this case, the rotator 120 preferably is integrated in such a manner that the rotator 120 is fixed on the driving shaft 210 by a key.

Furthermore, the other side of the driving unit housing 100 that is opened and opposite to the front bracket 112 is sealed by a rear bracket 114. The driving shaft 210 integrally combined with the rotator 120 through the center of the rear bracket 114 is disposed on the other side of the driving unit housing 100.

Here, in order for the driving shaft 210 to smoothly rotate, a front bearing 132 is interposed between the center of the rear bracket 114 and the driving shaft 210. A rear bearing 134 is installed at a point that is spaced apart from the front bearing 132 toward the propeller 220, so the driving shaft 210 is supported in such a way as to be smoothly rotated.

Accordingly, a portion surrounded by the front bracket 112 and the rear bracket 114 forms the driving unit housing 100, and the stator 110 and the rotator 120 are installed within the driving unit housing 100.

In such a structure, the present invention further includes a separation diaphragm 140 that fully partitions the stator 110 and the rotator 120.

As shown in FIG. 3, the separation diaphragm 140 is disposed to seal the stator 110 in the state in which the separation diaphragm 140 has been supported by the diaphragm bracket 150 and closely adhered between the diaphragm bracket 150 and the stator 110.

Through such a structure, the separation diaphragm 140, together with the rotator 120, forms a space, that is, an air gap of about 0.5 to 1.5 mm, thus not affecting the rotation driving of the rotator 120.

Furthermore, the separation diaphragm 140 fully separates the stator (110) side from the rotator (120) side, so water is fundamentally prevented from flowing into the stator 110 although the water is infiltrated into the stator 110 along the driving shaft 210.

For this reason, although the stator 110 equipped with electrical facilities, such as electric wiring, is placed under the water, safety is maximized because the stator 110 is fully protected against seawater. Furthermore, the driving shaft 210 can be smoothly driven because the separation diaphragm 140 does not come in contact with the driving shaft 210, and the remaining space S other than the driving shaft 210 contains infiltrated water although the infiltrated water flows along the driving shaft 210.

Here, the reason why the space S formed as described above and the separation diaphragm 140 are installed, that is, a very important concept, is that it is easy to seal a gap that is not moved, but it is evident that sealing between moving members is very difficult.

However, if the driving unit and the propulsion unit are integrated as in the present invention, the driving shaft 210 that is rotated needs to be connected up to the rotator 120 that forms the motor in order for driving force to be changed into propulsion force.

However, since the propeller 220 directly coming in contact with water under the water is attached to the driving shaft 210, water easily moves toward the rotator 120 and the stator 110 along the rotating driving shaft 210. In order to preclude the moving water, the driving shaft 210 is sealed several times, but it is not easy to seal the driving shaft 210 so that perfect water tightness is achieved because the driving shaft 210 is a moving body. In particular, it is not easy to implement sealing (watertight) close to perfection because the driving shaft 210 is equipment that is driven while being subject to water pressure under the water.

Moreover, when water leaks because of low water tightness, an electrical short, that is, a short, a spark, an electric leakage, etc., are generated in the stator 110. Accordingly, there is a danger of an electric shock accident and there is a very important problem that threats safety upon use under the water because the driving of equipment is stopped.

For this reason, to secure water tightness is important to the extent that it is no exaggeration to say that securing water tightness is a core of core techniques in the corresponding field.

In order to achieve water tightness, in the present invention, water tightness close to perfection is secured by forming the specific space S between the stator 110 and the rotator 120 and perfectly precluding a space between the stator 110 and the rotator 120 so that water introduced along the driving shaft 210 is stored in the space S in order to prevent the water from going over the stator (110) side and removed without simply placing the diaphragm.

Moreover, the driving shaft 210 is configured to be rotated and supported by the front and rear bearings 132 and 134 so that it does not penetrate the stator 110 unlike in the prior art, thereby further maximizing water tightness.

Furthermore, if a very small amount of water is introduced along the driving shaft 210, that is, a shaft, although a very small amount of water will not be introduced along the driving shaft 210 from a viewpoint of the structure of the present invention, the introduced water is easily dried by heat generated when the driving shaft 210, the rotator 120, etc. are rotated and moved. An orifice (not numbered) may be formed in part of the rotator 120 such that if the water is not dried, the water is drained from the space S to a space R within the rear bracket 114 and the spaces S and R communicate with each other.

Moreover, the present invention is configured not to have a problem because the rotator 120 is formed of a permanent magnet and electricity does not flow so that there is no influence although water is introduced into the rotator 120.

Furthermore, the space R is extended toward the outer circumference surface of the rotator 120, and the space R is formed of the diaphragm bracket 150 interposed between the driving unit housing 100 and the rear bracket 114 and the rear bracket 114.

In the worst case, a surface of the rotator 120 may preferably be subject to film coating processing (waterproof processing) so that the driving of the rotator 120 is not affected, that is, the function and durability of the magnet can be maintained, although water is infiltrated and the space S is fully filled with the water.

Meanwhile, the driving shaft 210 is disposed to penetrate a driving shaft housing 212 connected to the rear bracket 114, and the rear bearing 134 that rotatably supports the driving shaft 210 is embedded in the driving shaft housing 212.

Accordingly, the driving shaft 210 is supported in such a way as to be smoothly rotated by the front bearing 132 and the rear bearing 134 installed at the center of the rear bracket 114.

Furthermore, a seal housing 230 is connected to the rear end of the driving shaft housing 212, and a seal 232 coming in contact with the outer circumference surface of the driving shaft 210 is embedded in the seal housing 230 in order to prevent water from being introduced through sealing.

Furthermore, the propeller 220 is mounted on the outside of the seal housing 230, and a retainer 234 for precluding water introduced from the outside is further installed in order to perform another sealing.

Furthermore, a plurality of inlet holes 240 is formed in the outer circumference surface of the propulsion unit housing 200. Water introduced through the inlet holes 240 is sprayed to the rear of the submerged scooter through the propeller 220, thereby generating propulsion force.

Here, a diffuser 250 is installed in the inside diameter at the end of the propulsion unit housing 200 in order to improve propulsion efficiency by guiding and discharging a fluid in a straight-line direction. A bushing 260 is provided at the center of the diffuser 250, and the rear end of the driving shaft 210 is inserted into the bushing 260 and rotated and supported by the bushing 260.

As described above, in the present invention, in the state in which a watertight structure is formed of the retainer 234, the seal housing 230, the seal 232, etc. several times, the rotator 120 is formed of a permanent magnet, the additional separation diaphragm 140 is attached to the rotator 120 so that the rotator 120 and the driving shaft 210 are fully separated from the stator 110, and the space S is formed between the separation diaphragm 140 and the rotator 120. Accordingly, sealing almost close to perfection can be performed, and safety can be certainly secured when using the propulsion apparatus under the water.

In accordance with the present invention, in the propulsion apparatus for underwater driving in which the driving unit and the propulsion unit have been integrated, in particular, the stator and the rotator that form the driving unit are fully separated by the diaphragm. Accordingly, there are advantages in that perfect water tightness can be secured and thus a safe operation under the water is possible. 

1. A propulsion apparatus for underwater driving, comprising: a driving unit housing having a motor embedded therein; a propulsion unit housing connected to the driving unit housing, having a plurality of inlet holes formed therein in a radius direction, and comprising a propeller and a driving shaft for rotating the propeller; a motor supplying power to the driving shaft and comprising: a stator having a coil wound on a core; and a rotator having a permanent magnet, wherein one end of the driving shaft is integrally fixed to the rotator through a center of the rotator; a separation diaphragm separating the rotator and the stator; a diaphragm bracket supporting the separation diaphragm fixed thereto, and being fixed to the driving unit housing so that an air gap is provided between the separation diaphragm and the rotator; and wherein the end of the driving shaft remains spaced apart from the separation diaphragm, and part of one side of the rotator is concaved so that a space S is formed between the separation diaphragm, the driving shaft, and the rotator.
 2. The propulsion apparatus of claim 1, wherein the air gap is 0.5 to 1.5 mm.
 3. The propulsion apparatus of claim 1, wherein an orifice is formed on the rotator and configured to discharge water introduced into the space S to a space outside the rotator on an opposite side to the separation diaphragm.
 4. The propulsion apparatus of claim 1, wherein a surface of the rotator is subject to waterproof coating.
 5. The propulsion apparatus of claim 1, wherein the driving shaft is rotated and supported by a pair of front and rear bearings and integrally fixed to the rotator through a center of the rotator, and the stator is separated from the driving shaft. 